Hot melt adhesive system and method using machine readable information

ABSTRACT

A hot melt adhesive system includes a melting unit configured to liquefy a bulk form of hot melt adhesive and deliver the liquefied hot melt adhesive to an application location. The melting unit includes a controller for establishing and/or verifying at least one system condition, such as temperatures associated with system operation. A machine reading unit is coupled with the controller and is capable of receiving information from a machine readable element and communicating the information to the controller for use in establishing and/or verifying the system condition. A method of operating the system includes scanning information on at least one system condition into the controller from a machine readable element, and using the scanned information during operation of the melting unit.

CROSS REFERENCES

This application is a continuation of application Ser. No. 10/699,404,filed Oct. 31, 2003 (pending), the disclosure of which is herebyincorporated by reference herein in its entirety.

TECHNICAL FIELD

The present invention pertains to dispensing systems for dispensingflowable material, and more particularly to hot melt adhesive dispensingsystems.

BACKGROUND

Thermoplastic adhesives, otherwise known as “hot melt” adhesives havebeen widely used in industry for adhering many types of products. Hotmelt adhesive dispensing systems generally include a dispenser coupledwith one or more dispensing guns, heated hoses fluidly connected to theguns, and a melting unit for melting and supplying heated liquidadhesive to the guns through the heated hoses. The melting units ofconventional hot melt adhesive systems typically include a tank, aheater, a pump, a pump manifold, and a controller. The heater isgenerally located in a base of the tank for melting and heating adhesivematerial received into the tank in solid or semi-solid form. The pumpmanifold has an inlet connected to the tank and has multiple outletports adapted for connection to the heated hoses.

After the adhesive material is melted and heated in the tank, a pumpoperatively coupled to the tank and the pump manifold pumps liquidadhesive from the tank, through the pump manifold and heated hoses tothe dispensing guns. Typically, the guns are connected to their ownmanifold. The controller controls the power supplied to the tank heaterand heated hoses to maintain the liquid adhesive at an appropriateviscosity and temperature, depending on the application. The controlleris also used to control many other operations of the system.

Before an adhesive dispensing operation can begin, the operator mustensure that the system parameters are set to values that are appropriatefor the particular adhesive being used, as well as for the applicationneeds. As some examples, system conditions such as adhesive applicationtemperature, set back temperature, and over-temperature conditionsshould be set in the controller. If the system parameters areincorrectly set, various problems can arise such as overheating andcharring of the adhesive, or underheating of the adhesive which couldresult in operational problems and adhesive bonding problems. Variousother conditions may need to be set to establish a proper dispensingcycle. For example, there will be a delay time between when the systemis turned on and the time that actual dispensing can take place.

A need therefore exists for a hot melt adhesive dispensing system havingthe ability to better ensure that system parameters are properly set inthe controller. It would also be desirable to enable an operator to moreeasily and positively establish system conditions appropriate to theadhesive being processed, and efficiently utilize information related tosystem operation.

SUMMARY OF THE INVENTION

The present invention generally relates to a hot melt adhesive systemincluding a melting unit and a controller coupled to a suitable machinereading unit which can receive information from a machine readableelement and communicate that information to the controller. The meltingunit is configured to liquefy a bulk form of hot melt adhesive anddeliver the liquefied hot melt adhesive to an application location. Thecontroller establishes or verifies at least one system condition and theinformation received from the machine reading unit is used by thecontroller to verify or establish the system condition.

As examples, the machine reading unit may take the form of a bar codereader or magnetic strip reader, however any other machine readableelement and appropriate device for reading the element may be used. Thesystem condition or conditions which are established based on theinformation received by the machine reading unit can, for example,include the application temperature of the hot melt adhesive, anover-temperature condition of the hot melt adhesive, a set-backtemperature of the adhesive, or other conditions, such as warnings orparameters associated with a system flushing operation.

The invention further provides a method of operating a hot melt adhesivesystem having a controller operating a melting unit. The method includesscanning information on at least one system condition into thecontroller from a machine readable element, and using the scannedinformation during operation of the melting unit. Using the scannedinformation can further comprise setting appropriate temperatureconditions, warning conditions, system flushing parameters. Other usesinvolve collecting information such as adhesive identificationinformation or information indicating the amount of adhesive processedby the melting unit. Any information of the type used in carrying outthis invention may also be logged into a database for various diagnosticor analytical purposes. Preferably, the information is located directlyon the container in which the bulk hot melt adhesive typically ispackaged. This may involve, for example, a bar code or other machinereadable element affixed to or forming part of the container. Aconventional bar code scanner, magnetic strip scanner, or other devicemay be used which is appropriate for the machine readable element.

Various advantages are realized from this invention, including theability to quickly and positively download any necessary systemparameters associated with a particular system operational procedure ortype of adhesive. The parameters for each type of adhesive may becontained on the machine readable element associated with the bulkcontainer of the adhesive which is then scanned or read in just prior tosystem operation as opposed to relying on the operator to input suchinformation manually. Various system warnings may alert personnel if thetype of adhesive is changed during a manufacturing operation, or if thesettings are different than those recommended by the adhesivemanufacturer. By scanning or reading adhesive information, such as lotnumbers, into the controller, a defective lot of adhesive may be moreeasily identified. If each bulk container is scanned or read, then theamount of adhesive used in a given time period may be determined andtracked. Any or all information can be logged into a database forpurposes such as verifying that all adhesive types are being appliedunder the proper conditions. The invention further contemplates hot meltadhesive containers of bulk adhesive material having such machinereadable elements affixed thereto in any suitable manner allowinginformation to be input upon delivery of the container to an operator.

These and other features, advantages and objectives of the inventionwill become more readily apparent to those of ordinary skill in the artupon review of the following detailed description of the preferredembodiments, taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the invention and,together with a general description of the invention given above, andthe detailed description given below, serve to explain the details ofthe preferred embodiments.

FIG. 1 is a schematic drawing of a hot melt adhesive system, including amelting unit, controller and bar code scanner configured according toone illustrative embodiment of the present invention; and

FIG. 2 is a schematic drawing similar to FIG. 1, but illustrating analternative scanner and machine readable element of magnetic form.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The inventive principles will be described below in connection with aspecific description of a hot melt adhesive system 10, however, itshould be understood that the invention is applicable to many othertypes of systems and is not limited to the details described below. Thevarious components described below may be modified, eliminated, addedto, and generally assembled in many different manners.

Referring to FIG. 1, a hot melt adhesive system 10 includes a pair ofadhesive guns 12, 14, a dispensing unit 16 for supplying adhesive 18 tothe guns 12, 14, and heated hoses 20 connecting the dispensing unit 16to the guns 12, 14. Cord sets 21 are used to heat and control thetemperature of hoses 20 in a known manner. The dispensing unit 16includes a tank 22 for receiving and melting hot melt adhesive 18, amanifold 24 in fluid communication with the tank 22, a pump 26constructed according to the principles of the present invention andcoupled to the manifold 24, and a controller 28. The tank 22 comprisesside walls 30 and base 32 which includes a tank heater 34 for meltingand heating the adhesive material 18 in the tank 22. A tank outlet 36proximate the base 32 is coupled to a passage 38 which connects to aninlet 40 of the manifold 24.

The manifold 24 is located adjacent the tank 22 and includes a manifoldheater 42 that is separate from the tank heater 34 and which may beindependently controlled by the controller 28. Pump 26 is coupled to themanifold 24 and pumps liquid adhesive 18 from the tank 22, through afilter (not shown) removably disposed within the pump 26, and into themanifold 24. The manifold 24 splits the adhesive 18 into separate flows46 and directs the flows 46 to a plurality of outlet ports 48. Theplurality of outlet ports 48 are configured to be coupled to the heatedhoses 20 whereby the liquid adhesive 18 is supplied to the guns 12, 14.

The guns 12, 14 may be mounted to a frame 50 and include one or moreadhesive dispensing modules 52 which apply the adhesive 18 to a desiredproduct (not shown). Modules 52 may be coupled to their own manifolds 54for supplying adhesive, actuating air and process air thereto. The hotmelt adhesive system 10 illustrates two gun manifolds 54 each suppliedby a single hose 20, however, a second hose 20 is shown on each side ofsystem 10 and may supply additional gun manifolds (not shown) locatedrespectively behind manifolds 54. Other hot melt systems may have asingle gun, or may have other guns and the guns and other components ofthe system may take on many different configurations, according to theparticular adhesive dispensing requirements without departing from thescope of the present invention.

Still referring to FIG. 1, in accordance with one embodiment of thisinvention, a bar code reader or scanner 62 is coupled to the controller28 and is operable to read a conventional bar code label 64 which may,for example, be affixed to a bulk container 66 of hot melt adhesive. Thescanner or reader 62 may be hand held as shown, or may be fixed in placesuch that the container 66 may be brought within sufficient proximity toenable reading of the bar code 64 a. The bar code reader 62 is capableof receiving information from the bar code 64 a and communicating thatinformation to the controller 28 for use in establishing and/orverifying various system parameters or conditions. Typically theseconditions, such as adhesive application temperature, over temperature,setback temperature, as well as other setup conditions are inputted intothe controller 28 through various methods. For example, they may beentered manually through a control pad, as is conventional, or they maybe entered via a remote computer or other electronic device via anynumber of ways including, but not limited to, the Internet, an intranet,infrared devices, other wireless devices, memory cards, etc. Otherconditions may also be set based on information contained on the label64 or other machine readable element. For example, various dispensingcycle parameters may be set or verified relative to cycle times, on/offor dispensing time delays, etc. This includes various system warnings,adhesive information, and other data collection which may be used fordiagnostic or analytical purposes. The information obtained from thelabel 64 or machine readable element is electrically transmitted to thecontrol 28 via a cable 68 which may comprise a conventional programmablelogic controller (PLC) or other microprocessor based control systemconfigured to communicate with the bar code reader 62. Element 64 couldinstead be an embedded electronic chip which is readable via a portablewand or other reading device, or which is read upon coming intoproximity with such a reader which is part of system 10, such as withincontroller 28.

As illustrated in FIG. 2, one of many alternative types of machinereadable elements and scanners may comprise a suitable card 70 having amagnetic strip 70 a and a scanner or reader 72 configured to receive theinformation from the magnetic strip 70 a. The machine readable element,in this case being a card with a magnetic strip 70, may be separableand/or independent of the container 66 of hot melt adhesive. Forexample, an operator may be supplied with a card 70 detachable from thehot melt adhesive container 66, or the card 70 may be chosen by theoperator from a set of cards at the system workstation based on the setof parameters desired, for example, related to a particular type ofadhesive. The card 70 may transmit information to the control 28 inmanners such as those described above with respect to FIG. 1. All othercomponents shown in FIG. 2 have like reference numerals and thus havebeen described in connection with FIG. 1 as well. The present invention,and its various aspects, may be implemented using many other types ofmachine readable elements including, but not limited to, other elementswhich rely on any wireless communication technology, such as radiofrequency (RF) technology (such as RFID tags or transponders), WiFitechnology and magnetic devices of various types.

It will be appreciated that the present invention may be used in manydifferent manners to improve the operation of a hot melt adhesivedispensing system. By scanning (i.e., transmitting) the machine readableelement on the container of adhesive, such as a drum or other type ofcontainer, the particular operational parameters corresponding to thatadhesive may be automatically downloaded into the system controller 28.This minimizes the possibility of error in the system operationalparameters. In addition, process conditions can be verified with theoperator before operation of the system. For example, if a container isscanned and is providing different information from the previouslyscanned container, the control system can prompt the operator to confirmthat the change in adhesive is desired. This ensures that an incorrectadhesive is not inadvertently used in the middle of a manufacturingoperation potentially resulting in system downtime and product scrap. Inaddition, the system controller can track whether settings differentfrom those recommended by an adhesive manufacturer are being used duringoperation of the system 10 to assist with diagnosing maintenance orother problems with the system 10. During a system flushing operation,scanning a machine readable element with system flushing information canadjust the controller settings appropriate to the system flushprocedure. After the system flush, rescanning the adhesive containerlabel or other machine readable element associated with the particularhot melt adhesive, will return the controller 28 to the hot meltadhesive application settings. Finally, the controller 28 can alsoreceive information appropriate to tracking the amount and type ofadhesive being used in system 10. This can aid in determining whether aparticular lot or batch of adhesive was defective and track use of thesystem 10 for purposes of scheduling appropriate maintenance. Logging ofapplication data can provide confirmation and certification that theadhesive is being applied under the appropriate settings.

While the present invention has been illustrated by the description ofvarious embodiments thereof, and while the embodiments have beendescribed in considerable detail, it is not intended to restrict or inany way limit the scope of the appended claims to such detail.Additional advantages and modifications will readily appear to thoseskilled in the art. The invention in its broader aspects is thereforenot limited to the specific details, representative apparatus andmethods and illustrative examples shown and described. Accordingly,departures may be made from such details without departing from thescope or spirit of Applicants' general inventive concept.

What is claimed is:
 1. A method of operating a hot melt adhesivedispensing system having a controller operating a melting unit, themethod comprising: wirelessly receiving information from a machinereadable element identifying a hot melt adhesive to be dispensed, thecontroller utilizing the received information to set a system operatingcondition of the hot melt adhesive dispensing system, and operating thehot melt adhesive dispensing system according to the system operatingcondition to dispense the hot melt adhesive.
 2. The method of claim 1,wherein the information is received from a container of the hot meltadhesive.
 3. The method of claim 1, further comprising: opticallyreceiving the information from the machine readable element.
 4. Themethod of claim 1, further comprising: magnetically receiving theinformation from the machine readable element.
 5. The method of claim 1,further comprising: electronically receiving the information from themachine readable element.
 6. The method of claim 5, further comprising:receiving the information through a radio signal.
 7. The method of claim1, further comprising: receiving the information from an electronicchip.
 8. The method of claim 7, wherein said electronic chip is carriedon a container of the hot melt adhesive.
 9. The method of claim 8,further comprising: receiving the information from the electronic chipwith a portable machine reading unit.
 10. The method of claim 8, furthercomprising: receiving the information from the electronic chipautomatically when the container of hot melt adhesive comes withinproximity to the hot melt adhesive system.
 11. The method of claim 1,wherein utilizing the wirelessly received information further comprises:setting an application temperature of the hot melt adhesive.
 12. Themethod of claim 1, wherein utilizing the wirelessly received informationfurther comprises: setting an over-temperature condition of the hot meltadhesive.
 13. The method of claim 1, wherein utilizing the wirelesslyreceived information further comprises: establishing and/or verifying aset-back temperature of the hot melt adhesive.
 14. The method of claim1, wherein utilizing the wirelessly received information furthercomprises: setting a warning condition in the controller.
 15. The methodof claim 1, wherein utilizing the wirelessly received informationfurther comprises: setting a system flushing condition in thecontroller.
 16. The method of claim 1, wherein wirelessly receivinginformation further comprises: wirelessly receiving informationidentifying the hot melt adhesive processed in the melting unit.
 17. Themethod of claim 1, wherein utilizing the wirelessly received informationfurther comprises: determining an amount of the hot melt adhesiveprocessed in the melting unit.
 18. The method of claim 1, furthercomprising: logging the wirelessly received information into a database.19. The method of claim 1, wherein wirelessly receiving informationfurther comprises: wirelessly receiving information located on acontainer of the hot melt adhesive.